So the skinniest kids drink whole milk. Next larger size kids don't drink milk. Fattest kids drink medium- or low-fat milk. Whole-milk kids weighed an average of 4 kilos less, 9 pounds (less than no milk or skim milk?).
Researchers are scrambling for a reason.
"This is an interesting observation, but we don't know why it is so. It may be the case that children who drink full-fat milk tend also to eat other things that affect their weight. Another possible explanation is that children who do not drink full-fat milk drink more soft drinks instead," says dietician Susanne Eriksson, author of the thesis.
The scientists also discovered a difference between overweight children who drink full-fat milk every day and those who do not. Children who often drink milk with a fat content of 3% are less overweight. The thesis shows also that the children eat more saturated fat than recommended, but those children who have a high intake of fat have a lower BMI than the children with a lower intake of fat.Let me repeat that last independent clause: "those children who have a high intake of fat have a lower BMI than the children with a lower intake of fat."
Again Rule 1 rears its head: Everything is more complicated than you think it is. Maybe Eriksson's conjectures are right, or maybe some other weird thing is the reason, but it certainly is counterintuitive.